Crucial conventions:

• TPC sectors are numbered 1-24 by CSN0229A; looking along the beam at the origin from outside the TPC, the west-end sectors are numbered 1-12 like a clock; the east-end sectors are numbered similarly, 13-24 (with 24 at the top).

• RDO locations on each sector are numbered 1-6, with 1,2 on the inner subsector and 3-6 on the outer, by CSN0229A; there are 144 RDO's in all.

• Each RDO location has a unique 8-bit ID number. The ID represents RDO position RRR=[1,6] on sector SSSSS=[1,24] as SSSSSRRR. 144 of the 256 possible 8-bit codes are legal.

• Each sector has 181 FEE cards, uniquely identified by an 8-bit ID etched into the padplane. The ID's decrease with radius (in contrast to the RDO and padrow ID's defined later):
  • 0-125 on the outer subsector
  • 126 does not appear (for historical reasons)
  • 127-181 on the inner subsector

References on FEE and RDO conventions:

• Controlled STAR Note SN0229A by H. Matis et al.

• Front-End Electronics -> DAQ Fiber Interface, (Req. Doc., V1.2, April 10, 1996), by V. Lindenstruth et al.

• STAR Electronics Cable Summary by H. Matis and B. Minor (SN0378).